
public class Bottle<T extends Drink> {
	
	public T content;
	
	public boolean isEmpty(){
		return content==null;
	}
	
	public void fill(T content){
		if(isEmpty()) {this.content=content; return;}
		throw new IllegalArgumentException();
	}
	
	public T empty(){
		if(isEmpty()) throw new IllegalArgumentException();
		T temp = content;
		content = null;
		return temp;
	}
	
}
